Dental apparatus



Nov. 6 {31923.

M. F. BURNS DENTAL APPARATUS Filed Safat. 2, 192 2 IN VEN TOR A TTORNE Y Patented Nov. 6, i923.

siren re MARTIN E. BURNS, ASTORIA, NEW YORK.

DENTAL APPARATUS.

Application filed September 2, 1922. Serial No. 585,884.

To all whom it may concern:

Be it known that I, MARTIN F. BURNS, a citizen of the United States, and a resident of Astoria, county of Queens, and State of New York, have invented certain new and useful Improvements in Dental Apparatus, of which the following is a specification.

This invention relates to dental apparatus and more particularly to dental flasks and to investment holders used in casting plates, bridges, inlays and other restorations.

In casting a plate, bridge or other restoration a dentist first makes a pattern in Wax of the article to be cast. The pattern is then placed in an investment holder and is invested in an initially plastic and quick hardening composition. When the investment is dry or has set the wax is melted out or otherwise dissipated and the cavity is filled with molten metal. The metal is forced into the cavity under pressure to eifect the complete filling of the cavity. The casting is then allowed to cool and is preferably cooled slowly to prevent warping or distortion.

When the apparatus is used for casting inlays, the casting is comparatively small and therefore it is desirable to use a small investment holder. This saves investment and greatly expedites the making of the casting since the wax pattern can be quickly melted out and the metal can be poured and will cool in a very short space of time.

One of the objects of the invention is to provide apparatus of the class described so constructed and arranged as to expedite the making of small castings.

Another object of the invention is to provide a receptacle'for dental casting apparatus so constructed as to be adapted for use with. a plurality of sizes of investment holders.

Another object of the invention is to provide a plurality of investment holders of different capacity and so constructed that they can be used with the same receptacle.

Further objects of the invention will appear from the following description taken in connection with the drawings which form a part of this applicationand in which,

Fig. 1 is a top plan view of dental apparatus constructed in accordance with the invention and comprising a receptacle and an investment holder disposed therein.

Fig. 2 is an elevational view, partly in section, of the construction shown in Fig. 1.

Fig. 3 is a view similar to Fig. 2 but showing an investment holder of smaller capacity mounted in the receptacle.

Fig. 4 is a view similar toFigs. 2 and 3 but showing another size of investment holder.

Fig. 5 is a top plan view similar to Fig. 1, but showing another shape of receptacle and investment holder, and

Fig. 6 is a top plan view showing still another shape of investment holder.

The invention briefly described comprises a receptacle having means such as a ledge or flange projecting inwardly therefrom for supporting an investment holder, the investment holder having a portion such as a laterally extending flange adapted to rest or seat on the supporting means of the receptaele.

Referring to the drawings, there is shown a receptacle 10, tubular in form and in the embodiment shown in Figs. 1-4., substantially cylindrical in shape. The receptacle 10 is open at its two ends and has formed thereon intermediate the ends an inwardly projecting ledge or flange 1]. having an open in therethrough.

The investment holder comprises a tubular member 12 having formed on one end thereof a laterally extending flange 18 adapted to rest or seat on the ledge 11 of the receptacle.

From the showing in the drawings it will be noted that the ledge 11 is recessed to receive the flange 13 of the investment holder, whereby the holder will be positioned or centered and the upper surfaces of the ledge 11. and flange 13 will be flush. v

By so constructing and arranging the receptacle and investment holder, holders of different capacity may be used in connection with one receptacle. In Fig. 3 the investment holder 12 is smaller in size 'or capacity and has a wider flange at its upper end thereby adapting this holder to be supported on the ledge. 11 of the receptacle 10. In Fig. 4:, the holder 12 is still smaller in capacity and has a still wider flange adapted to rest on the ledge 11 of the receptacle.

The receptacle and investment holder may be made of any desired shape or contour and in Fig. 5 both the receptacle 20 and the investment holder22 are elliptical in shape In Fig. 6 the investment holder is substantially cylindrical and the investment holder has a circular flange 31 and an elliptical body portion 32.

It will be understood that the shape of the investment holder and the size thereof to be used will depend on theshape and size of the casting to be made.

.The apparatus above described is particularly adapted for use in making small castings such as dental inlays and because of the fact that relatively .small investment holders can be used, the amount of investment necessary is reduced to a minimum and furthermore becauseof the smaller amount of investment the wax pattern can be quickly melted or dissipated and the casting can be'made'in a very short space of time. 7 I

Although certain specific embodiments of the invention have been illustrated and deinwardly extending flange thereon and disposed intermediate the ends thereof, and an investment holder supported on said flange.

3. In'combination, a receptacle havlng an inwardly extending flange-thereon and disposed intermediate the ends thereof, and an investment holder having a flange supported on said flange.

4. In combination, a substahtiallycylindrical receptacle having an inwardly extendingflange thereon disposed intermedi'- ate' "the ends thereof, and an investment holder supported on said flange.

In combinatiomfa substantially cylindrical, open ended receptacle having an inwardly extending flange thereon disposed intermediate the ends thereof, and an .-investment holder supported on said flange.

6. In combination, a substantially cylindrioal receptacle having an inwardly extending flange thereon and disposed intercdrical receptacle having an inwa-rdly'exmediate the ends thereof, and an investment holder supported on said flange. r

7. In combination, a substantially cylintending flange thereon and disposed intermediatethe ends thereof, and an investment holder supported on said flange.

8; In combination, 1 a receptacle having means extending inwardly from its inner supporting an investmentv holder and an investment holder having means for engaging said supportingmeans.

9. In combination, an-openended recep tacle having .means extending inwardly from its inner surface for supporting an investment holder and an investment holder having means at its upper end for engaging'said supporting means. '7 r 10. In combination, an open ended, tubular receptaclehaving means extendinginwardl y fromits inner surface for supporting anin-vestment holder and; an investment holder having means at its upper end for en gaging, said supporting means.

11. Dental apparatus ,comprising a receptacle having u an inwardly extending ledge and an investment holder extending downwardly therefrom.

12. Dental apparatus comprising a'substantially cylindrical receptacle having an inwardlyiextending ledge and aninvestment holder extending downwardly therefrom.

18. Dental apparatus comprising a substantially cylindrical receptacle having an inwardly extending ledge and a tubular investment holder extending downwardly therefrom.

14:. In combination, a receptacle having an inwardly extending recessed. flange thereon, and an investment holder having a flange supported on said flange and seated insaid recess. Y Y

15. In combination, a receptacle having an inwardly extending ledge thereon, said ledge having. an annular recess, and an'investment holder supported on said ledge and l positioned by said recess. p

In witness whereof I have hereunto set 100 my hand this 28th dayof August, 1922.

. MARTIN F. BURNS.

surface intermediate the ends thereof for 

